Tapping unit having thread means for attachment thereof to a container



Aug. 1, 1967 MOLINEUX 3,333,737

TAPPING UNIT HAVING THREAD MEANS FOR ATTACHMENT THEREOF TO A CONTAINER Filed on. 12. 1965 Fig. 1.

9% wax 49 3,333,737 TAPPING UNIT HAVING THREAD MEANS FOR ATTACHIVIENT THEREOF TO A CONTAINER Levi Molineux, Hamilton, Brisbane, Australia {P.O. Box 239, Surfers Paradise, Queensland, Australia) Filed Oct. 12, 1965, Ser. No. 495,275 1 Claim. (Cl. 22291) This invention relates to a tapping unit for fluid containers, particularly containers such as cans or plastic containers which have thin walls.

One object of the invention is to provide a fluid passage from the container for dispensing the fluid. The device of the invention pierces the container, enlarges the hole and seals tightly in the enlarged hole to act as a fluid passage from the container. The device is usually, although not necessarily, provided with a tap to control fluid flow.

The tapping device of the invention is reusable.

In tapping thin material, one difficulty is that the material tends to split unevenly as the tapping hole is enlarged and there is a danger of leakage through the splits.

It is an object of the invention to avoid this, by controlled enlargement of the tapping hole and positive pressure sealing around the enlarged hole.

Accordingly, the invention comprises a container tapping device including a hollow body, an outlet from said body at one end thereof, a piercer point extending from the other end of said body, an external thread of increasing diameter on said body leading from said piercer point, an inlet to the interior of said body and sealing means movable relative to said body to exert external pressure on a container surface engaged in said thread.

In order that the invention may be better understood an exemplary embodiment will now be described with reference to the accompanying drawings, in which:

FIG. 1 shows a general view of a tapping device.

FIG. 2 shows the device partly in section, with a claw assembly attached.

FIG. 3 shows a modified detail of the arrangement of FIG. 1 to enlarged scale, and

FIG. 4 shows partly in section a modified form of tapping device.

The unit shown is particularly suitable for tapping a sheet metal or thin plastic container 9 for liquids and provides a tap for dispensing the liquid therefrom. The unit includes a steel piercer point 10, an enlarging thread 11, leading via a square thread 12 to a hollow cylindrical body 13, the body 13 having an outlet to a T-pipe 15 which is provided with a tap 16.

Sealing means generally designated 17 is threaded on the body 13 to exert external pressure on the surface of the container in operation and seal it.

The piercer point 10 is preferably of tapered polygonal section, so that the container material tends to part at the sharp edges and roll up neatly against each face. The enlarging thread 11 has preferably a concave arcuate groove section 18 with cusps 19 between the grooves. This thread shape enables the rolled material to be retained firmly in the groove and the hole in the container to be enlarged in a controlled manner without any tendency to split radially.

Thread 11 leads directly into square constant-diameter thread 12, in which the enlarged hole engages and by which the unit is screwed into the container without further enlargement.

Thread 12 is preferably of constant pitch up to its last turn 20, bounded by the sealing means 17. Turn 20, however, is made of zero pitch, i.e. its plane is normal to the axis of the body 13. When the hole in the container reaches turn 20, it therefore lies loosely within it at right angles to the body 13.

The sealing means 17 includes a threaded collar 21,

- United States Patent tit) having wings or other projections 22 by which it can be t1 ghtened by hand, a rigid washer 23 and a resilient washer 24 adjacent turn 20. With the container hole lying in turn 20, collar 21 may be screwed down to press the resilient washer 24 against the external surface of the container and seal it, at the same time flattening the rolled edges, as shown in FIG. 3.

Grooves 24A may be provided in washer 24 to aid the sealing action.

In operation, piercer point is forced through container 9 either directly by using the T-pipe as a handle, or by leverage on a beaded edge 25 using a bifurcated claw assembly 26 attached to the body by washer 23 as shown in FIG. 2, and extending parallel to the axis of the body towards piercer point 10. The unit is then rotated to screw into the container, thread 11 enlarging the hole in controlled manner as described, and the enlarged hole finally seating in turn 20, as shown in FIG. 3.

In this position, radial holes 27 provide an inlet to body 13 for liquid within the container.

Collar 21 of sealing means 17 is then screwed down to compress the rolled edges of the container 9 between the lower edge of turn 20 and washer 24 and provide an effective seal.

Liquid may then be dispensed via tap 16 from the container.

As so far described, the unit cannot be removed from the container by unscrewing it owing to the zero-pitch turn 20 which makes it difiicult to re-engage the edge of the hole on thread 12. This is usually of'no importance where the unit is used with containers which are expendable, since the unit can be freed by releasing sealing means 17 and rocking the unit to split the edges of the hole.

However, the unit can be made to screw out nondestructively by a slight modification of the thread 12, as illustrated in FIG. 3.

The land 30 between the zero-pitch thread 20 and the pitched thread 12 is essentially sharp-edged. The edge 31 may be deflected slightly upwards towards the turn 20 as shown. Then, if pressure from sealing means 17 is released and the unit unscrewed, the edge 31 may be made to engage over, rather than under, the edge of the container hole and the unit may be removed by further unscrewing.

In a further modification, the width of the thread 12 may decrease as the thread passes towards the turn 20, so that the edges of the container material are gradually pressed together in travelling towards turn 20. The pitch of thread 12 may be made to decrease towards turn 20 to give a more gradual lead into turn 20.

Referring to FIG. 4, the device there shown is similar in general to that described with reference to FIGS. 1-3, having a piercer point 10 and an enlarging thread leading to a hollow body 13 with an outlet to a T-piece 15 and inlet holes 27. However, in FIG. 4 the expanding thread designated leads directly on to the body, the constantdiarneter thread 12 of FIGS. l-3 being omitted.

Body 13 of FIGS. 1-3 is divided in FIG. 4 into an upper internally threaded part 41 and a lower part 42, screwed together by an external thread on a reduceddiameter extension 43 on part 42. A resilient washer 44 is loosely mounted on extensions 43 and is backed by a rigid backing washer 45 having a part-spherical central boss 46 lying within a part-spherical recess 47 in part 41. Backing washer 45 is loosely fitted round extension 43 and has a limited ball-and-socket angular movement within recess 47, so that it may press washer 45 tight against a container surface even when the tapping device is inserted slightly crooked into the container or the container surface is uneven.

FIG. 4 also illustrates a modification by which a container such as a large can of beer may be re-pressurised.

The T-piece of FIG. l'is modified to have a tap 49 at one end and a gas pressure line connection 50 at the other. The handle 51 operates a two-way valve (not shown) of suitable type whereby the outlet passage 52 in the body part 41 is connected to tap 49 for dispensing fluid or to connection 50 for repressurising the container or is isolated from both (off position).

The expanding thread 40 is of right-triangular section, having'its lower face normal to the axis of the body. The uppermost turn therefore presents a flat face to the undersurface of the container in a similar manner to the turn in FIGS. 1-3.

In operation, the point 10 pierces the container and thread 40 is screwed in until the washer 44 contacts the outer surface. The ball-and-socket mounting at 46 of backing washer 45 and the looseness of washers 44, 45 on extension 43 allows a good seal in spite of crookedness of insertion or unevenness of the container surface. The final sealing pressure is obtained by take up of the thread on extension 43, if necessary.

Although the invention has been described so far as a tapping device for extracting fluids from containers, an equivalent device may be used without the fluid outlet to attach a hook or eye to a large container (such as a drum) for suspension or handling by ropes or chains since the device seals firmly on the container, such suspension means may be attached at almost any position on the container.

What I claim is:

A container tapping device including a hollow body comprising an upper part formed with a laterally extending internally threaded section the outer end of which defines a partially spherical internal seat, a lower part externally threaded at one end for threaded mounting in said upper part, said lower part of said body being formed with inlet openings adapted to intercornmunicate the hollow interior of said body and the container contents, an outlet from the upper part of said body at one end thereof for dispensing fluid therefrom, a tapered piercer point formed at the free end of said lower part of said body for piercing the wall of the container from which the fluid is to be dispensed, said lower part of said body being formed with an external thread formation of increasing diameter starting adjacent said piercer point for gradually enlarging the opening in the wall of said container started by said piercer point, sealing means disposed on said lower part of said body rear- Wardly of said thread formation, the innermost thread of said thread formation on said body being spaced from said sealing means for receiving and sealing the wall of said container, said sealing means comprising a resilient washer and a rigid, dish-shaped backing washer loosely disposed around said lower part of said body for limited transverse movement relative thereto, said rigid backing Washer having a partially spherical central boss complemented to said seat formed in said upper part of said body rotation of said upper part of said body relative to said lower part serving to clamp and seal the wall of said container around said enlarged opening formed in said container by said thread formation, the loose disposition of said rigid backing washer around the lower part of said body permitting a good seal despite lack of normality of said lower part of said body relative to said container wall.

References Cited UNITED STATES PATENTS 105,818 7/1870 Lord 222-91 477,308 6/ 1892 McFarland 222-91 766,083 7/ 1904 Watts 222-90 941,210 11/1909 Thompson 222-90 1,295,937 4/ 1919 Staiford et al. -50 1,309,167 7/ 19 19 Wyatt 222- 1,328,104 1/1920 Servis 222-91 2,015,158 9/ 1935 Rosenberg 222-91 2,184,263 12/1939 Adler 222-91 FOREIGN PATENTS 3,243 12/1861 Great Britain. 7,233 3/1912 Great Britain. 185,108 10/ 1923 Great Britain. 202,240 8/1923 Great Britain.

WALTER SOBIN, Primary Examiner. 

